Tag: Environment

Study eyes link between giant Tibet avalanche and global warming

Lubrication by meltwater may have enabled massive slide

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Credit: NASA Earth Observatory images by Joshua Stevens and Jesse Allen, using Landsat data from the U.S. Geological Survey, Sentinel data from the European Space Agency, and ASTER data from NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team.

Staff Report

Although the world’s ice and snow is melting rapidly on a geologic time scale, it still seems to be a gradual process, at least for casual observers. But last summer, July 16, to be exact, 70 million tons of ice broke off the Aru Glacier in western Tibet and crashed far down into the valley, killing nine nomadic yak herders. NASA scientists reported on the avalanche here.

A team of scientists who analyzed the giant avalanche now say there’s a good chance that global warming was a key factor in the unusual slide. The researchers, who published their findings this week in the Journal of Glaciology, said that that the avalanche lasted about four or five minutes, burying 3.7 square miles of the valley floor in that time. Something — likely meltwater at the base of the glacier — must have lubricated the ice to speed its flow down the mountain, they said. Continue reading “Study eyes link between giant Tibet avalanche and global warming”

At the nexus of climate change and invasive species

What happens when the trout streams warm?

A palm-size brook trout, caught in the Tenmile Creek drainage near Copper Mountain.
A palm-size brook trout, caught in the Tenmile Creek drainage near Copper Mountain. @bberwyn photo.

Staff Report

U.S. Geological Survey scientists have completed one of the first experimental studies to explore links between climate change and invasive species, specifically how  brook trout and brown trout interact with rising stream temperatures. They found that non-native browns limit the ability of brook trout to use warmer water temperatures, By contrast, removin of browns brook trouts’ reach into warmer waters.

Brookies are freshwater fish native to eastern North America and threatened by climate change because of their requirement for cold stream temperatures. Brown trout are native to Europe and have been introduced all around North America. Continue reading “At the nexus of climate change and invasive species”

Around the world with Summit Voice

Links to our climate and international news reporting …

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How much longer will the cryosphere last? @bberwyn photo.

By Bob Berwyn

Not as much content as usual on Summit Voice this week, but that’s because we were busy reporting elsewhere, with a few noteworthy stories. For example, Austria is holding a presidential election tomorrow (Sunday, Dec. 4) and the election of Donald Trump became an issue in the last few weeks of the campaign. I co-reported a story on the election with the European bureau chief of the Christian Science Monitor, including an interview with an American expat involved in the campaign.

Also published did a couple of pieces for Pacific Standard, including a photo essay on the Earth’s vanishing cryosphere, and an in-depth story about how the incoming Trump administration could undermine the integrity of science-based decision making in government agencies. Another article from a couple of weeks ago in Pacific Standard took a look at whether the world can still achieve the goals of the Paris climate agreement if the U.S. withdraws.

And at InsideClimate News, I reported on potential climate change links to the devastating wildfires in the Southeast, as well as on a new study suggesting that heat-trapping greenhouse gas pollution is shifting the track of Atlantic hurricanes to the north, where they are more likely to hit the Northeast coast.

I also took a close look at Germany’s ambitious new climate action plan, which aims to decarbonize the country’s economy by 2050. Absent U.S. leadership on climate policy, other major western industrial countries will have to lead by example.

Life under the ice

Scientists eye winter ecosystems in ice-covered lakes

Pond glow.
Evening glow on a the slowly melting surface of Dillon Resevoir, in Summit County, Colorado. @bberwyn photo.

Staff Report

A team of international scientists who studied more than 100 lakes during the winter said there’s more going on beneath the ice than we realized. Their findings stand to complicate the understanding of freshwater systems just as climate change is warming lakes around the planet, and shortening the ice season on many lakes. Other parts of the planet’s cryosphere are also melting under the thickening layer of heat-trapping greenhouse gas pollution.

“As ice seasons are getting shorter around the world, we are losing ice without a deep understanding of what we are losing,” said Stephanie Hampton, a Washington State University professor and lead author of a new study published in the journal Ecology Letters. “Food for fish, the chemical processes that affect their oxygen and greenhouse gas emissions will shift as ice recedes.” Continue reading “Life under the ice”

NASA study shows link between Deepwater Horizon spill and coastal wetlands erosion

A NASA satellite image shows the oil slick from the Deepwater Horizon disaster spreading across the northern Gulf of Mexico in late May, 2010.
A NASA satellite image shows the oil slick from the Deepwater Horizon disaster spreading across the northern Gulf of Mexico in late May, 2010.

‘Dramatic, widespread shoreline loss …’

Staff Report

Oil washed toward shore after the 2010 Deepwater Horizon disaster is a big factor in coastal erosion rates, according to scientists with NASA and the U.S. Geologicial Survey who tracked the changes along the Gulf of Mexico. Their research shows a pattern of dramatic, widespread shoreline loss” along  the Louisiana’s coast in Barataria Bay, located on the western side of the Mississippi River Delta.

The study compared images of the shoreline  taken a year before the oil spill with images taken during a 2.5 year span after the spill. Scientists also compared shoreline losses from storm-induced erosion with losses linked to shoreline oiling. Storm-induced erosion occurred at isolated shoreline sections, but the pre-spill shoreline from 2009 to 2010 was largely stable. Continue reading “NASA study shows link between Deepwater Horizon spill and coastal wetlands erosion”

Study IDs new parasite threat to honeybees

Detection could enable early intervention

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Pollinators are facing a broad range of threats, from pesticides and disease, to a new species of harmful parasites. @bberwyn photo.

Staff Report

There could be more trouble ahead for pollinators, as a new species of Varroa mite is developing the ability to parasitize European honeybees. That’s a new threat for insects already under pressure from pesticides, nutritional deficiencies and disease, according to a Purdue University study.

The scienists found some populations of Varroa jacobsoni mites are shifting from feeding and reproducing on Asian honeybees, their preferred host, to European honeybees, the primary species used for crop pollination and honey production worldwide. To bee researchers, it’s a grimly familiar story: V. destructor made the same host leap at least 60 years ago, spreading rapidly to become the most important global health threat to European honeybees. Continue reading “Study IDs new parasite threat to honeybees”

October ends up as 3d-warmest for Earth

Year-to-date still on record-breaking pace

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Record warmth has spanned the globe in 2016.

Staff Report

The average global temperature for October 2016 was 1.31 degrees Fahrenheit above the 20th century average, putting the month in a tie with 2003 for the third-warmest October on record.

Including 2016, the past three Octobers have been the three warmest in the historical record, but with the globe cooling down slightly from an El Niño heat surge, the monthly anomaly was the lowest deparature from average since Nov. 2014, according to the latest global monthly state of the climate report from the NOAA National Centers for Environmental Information. Continue reading “October ends up as 3d-warmest for Earth”